Final answer:
The joule (J) is the unit of measurement for work and energy, and the watt (W) is the unit of measurement for power. Watts measure the rate at which energy is used or given off per unit time, specifically in joules per second.
Step-by-step explanation:
The Joule and the Watt
Does the name Joule sound familiar? The joule (J) is the metric unit of measurement for both work and energy. The measurement of work and energy with the same unit reinforces the idea that work and energy are related and can be converted into one another. 1.0 J equals 1.0 newton-meter (N·m), which are the units of force multiplied by distance. Moreover, since 1.0 newton (N) equals 1.0 kilogram-meter per second squared (kg·m/s²), it also follows that 1.0 J equals 1.0 kilogram-meter squared per second squared (kg·m²/s²).
On the other hand, the watt (W) is the standard unit of measurement of power, which represents energy used or given off per unit of time. It is measured in joules per second (J/s). For instance, a 100-watt light bulb uses 100 joules of energy every second. In the context of electric energy, power companies typically use the kilowatt-hour (kWh) to measure the electric energy provided.
It's also worth noting that energy can be measured in calories, especially when discussing food energy. However, in scientific contexts, the joule is the standard unit of energy.